The truth is that Rogue One commits the same sin as most modern action movies: there is too much action.But this isn't to pick on that blog, you've probably had similar conversations with your friends.
As a result, you can't really tell much about the characters, as they spent 95% of their time being shot at, shooting people, or running away from stuff. The characters certainly seemed serviceable enough, though I don't really remember their names or much about them.
But this ignores that in an action movie, the action is the characterization. Part of what has made Star Wars so memorable hasn't been intricate monologues and flackbacks of backstory or other humanist fare, but rather extremely good and brief archetypes. Boba Fett is the epitome of this, but really you have Lando, Palpatine (in the OT), Tarkin, Greedo, Ewoks, Admiral Akbar, Wedge Antilles, General Grievous, Mace Windu, Boss Nash, even Jabba the Hutt. None of these are characters with a "rich backstory" but their character design and costume and appearance gave us a bright image that could stick with us. We don't know Boba Fett's internality, we just know that he is really cool.
Rogue One does this with the entire cast. It plays to Star Wars' strengths.
As proof of concept, I'm going to list what we know about these "shallow" characters, just from the brief action they get.